"Attacking-Attacking" Anti-biofouling Strategy Enabled by Cellulose Nanocrystals-Silver Materials
Victor T Noronha1,2, Jennifer C Jackson1, Camilla H M Camargos3
1Engineering School of Sustainable Infrastructure & Environment, Department of Environmental Engineering Sciences, University of Florida, Gainesville, Florida 32611-6540, United States.
ACS Applied Bio Materials
|February 18, 2022
Summary
This study combines cellulose nanocrystals (CNCs) with silver nanoparticles (Ag) to create advanced anti-biofouling surfaces. The new CNC/Ag material effectively kills both attached and free-floating bacteria, enhancing protection for various applications.
Area of Science:
- Materials Science
- Nanotechnology
- Biomedical Engineering
Background:
- High-performance anti-biofouling surfaces are crucial for preventing bacterial attachment and biofilm formation in critical applications.
- Cellulose nanocrystals (CNCs) are sustainable nanomaterials with antimicrobial properties, primarily acting through contact-mediated mechanisms.
- Limitations exist in CNCs' ability to target planktonic bacteria, necessitating enhanced antimicrobial strategies.
Purpose of the Study:
- To develop and evaluate a novel anti-biofouling surface by combining cellulose nanocrystals (CNCs) with silver nanoparticles (Ag).
- To enhance the antimicrobial efficacy of CNCs against both attached and planktonic bacterial cells.
- To elucidate the synergistic antimicrobial mechanism of the CNC/Ag composite material.
Main Methods:
- Fabrication of CNC/Ag composite material for surface coating.
- Quantitative assessment of anti-biofouling performance against attached bacteria (e.g., Escherichia coli, Bacillus subtilis).
- Determination of minimum inhibitory concentrations (MICs) for planktonic bacterial inactivation.
- Investigation of the bacterial inactivation mechanism using lipid vesicle assays and analysis of cellular damage.
Main Results:
- CNC/Ag-coated surfaces demonstrated superior inactivation of attached bacteria (>99%) compared to pristine CNCs (66.9% for E. coli, 32.9% for B. subtilis).
- CNC/Ag exhibited potent toxicity to planktonic cells with MICs of 25 μg/mL for B. subtilis and 100 μg/mL for E. coli.
- Evidence suggests a dual "attacking-attacking" mechanism involving physical membrane disruption by CNCs and intracellular damage by silver ions.
Conclusions:
- The combination of CNCs and silver nanoparticles creates a highly effective anti-biofouling material with enhanced antimicrobial activity.
- The synergistic mechanism involves CNCs physically disrupting bacterial membranes, facilitating silver ion entry and subsequent intracellular damage.
- This novel CNC/Ag composite holds significant promise for applications requiring robust control of bacterial contamination.
